1. Field of the Invention
The present invention relates to a spacer jig for replacing the spacer damper, which is installed on a four-conductor or six-conductor system, which are formed a set of power cables, and a method for replacing the spacer damper by setting the spacer jig. More particularly, the spacer jig is used as a tool to replace a damaged or bad spacer damper with a new one during the maintenance of the overhead power lines for reducing the vibration problems.
2. Description of the Related Art
In the conventional method of replacing the spacer damper, the worker travels high in the air with a new replacement spacer damper and installs it by temporarily assembling four conductors at a point 1 to 1.5 m away and six conductors about three m away from the spacer damper to be replaced, and then pushes this in close to the spacer damper.
This process has a problem of taking a long time since it is difficult to separate the spacer damper and replace it with a new one because the surface of the cable is damaged and a high tensile force is on the cable when the worker pushes in the spacer damper.
In order to replace the existing damaged spacer damper, the worker is lifted high in the air with a new spacer damper, and temporarily assembles the new spacer damper at a location about one to three m away from the existing spacer damper. The existing spacer damper cannot be approached closely enough to be replaced and the worker cannot hold up or widen the relevant cables by hand because of the high tensile force of the cable.
Because of that, the worker holds up the relevant cable by hand at a location where a certain degree of modification is possible, that is, a location separated by a given distance from the damaged spacer damper, before he temporarily assembles the new spacer damper.
The new spacer damper assembled temporarily like this should now be moved to the location of the existing spacer damper which is to be replaced. Since the location of the existing spacer damper was initially set up at the most suitable and efficient location with respect to the total length of overhead line, it is most preferable to install the new damper at the same location. Therefore, the new spacer damper is moved to and installed in the place where the existing spacer damper is located.
Considerable scratching can occur on the surface of the cable in the course of sliding the temporary spacer damper assembly as described above. It is also very difficult and dangerous for the worker high up in the air to push the spacer damper by hand for installation.
Moreover, the course of replacing one spacer damper in the cables consumes a lot of time, which gives rise to the problems of increased worker fatigue, decreased work effort and much lowered safety.
Especially for hot-line work of transmission lines, work safety decreases as working time increases, so it can be said that spacer damper replacement work using a spacer jig is a required process for hot-line work.